A communications network for reliable data transfer from a first node and a second node via two channels. A first unreliable channel transfers data according to an unreliable communications protocol such as RTP. A second reliable channel transfers the same data according to a reliable communications protocol, such as TCP. At the second node, data parts missing from the data received from the first node via the unreliable channel is detected and corresponding data parts received from the first node via the reliable channel used. The RTP channel may be operated over UDP over multicast or unicast. The TCP channel may be supplemented by a multicast group or a peer-to-peer network.